JP4697144B2 - Epoxy resin composition for prepreg, prepreg, multilayer printed wiring board - Google Patents

Description

  The present invention relates to an epoxy resin composition for a prepreg used for the production of a printed wiring board including a multilayer printed wiring board, a prepreg using the epoxy resin composition for a prepreg, and a multilayer printed wiring board using the prepreg. In particular, the present invention relates to a printed wiring board for plastic packages and a printed wiring board for cards.

  Flame retardant epoxy resins are used in various electrical insulating materials for reasons such as excellent self-extinguishing properties, mechanical properties, moisture resistance, and electrical properties.

  Conventional flame-retardant epoxy resins contain a halogen-based compound mainly composed of bromine for imparting flame retardancy, whereby the molded product has self-extinguishing properties. However, when such a molded product burns in a fire or the like, there is a risk that a compound that affects the human body such as polybrominated dibenzodioxin and furan may be formed. Moreover, a bromine-containing compound is one in which bromine decomposes when heated, resulting in poor long-term heat resistance. Therefore, there has been a demand for the development of a molded product having excellent flame retardancy and heat resistance without adding a halogen-based compound.

  In response to this demand, flame retardancy using mainly phosphorus element (phosphorus compound) has been studied. For example, an appropriate amount of an additive-type phosphorus flame retardant such as triphenyl phosphate (TPP), tricresyl phosphate (TCP), cresyl diphenyl phosphate (CDP), etc., which is a phosphate ester compound, is blended in an epoxy resin composition. By doing so, it becomes possible to ensure flame retardancy. However, since such an additive-type phosphorus flame retardant does not react with an epoxy resin, chemical resistance such as solder heat resistance and alkali resistance after moisture absorption of the obtained molded product is greatly reduced. A new problem has arisen.

  To solve the above problem, as disclosed in JP-A-4-11662, JP-A-11-166035, JP-A-11-124489, etc., a reactive type that reacts with an epoxy resin as a phosphorus compound. It has been proposed to use phosphorus flame retardants. However, when such a phosphorus compound is used, the moisture absorption rate of the obtained molded product becomes larger than that of the molded product obtained using the halogen compound, and the molded product becomes hard and brittle, and the solder heat resistance after moisture absorption is increased. Decreased. In addition, when a general epoxy resin such as a bisphenol A type epoxy resin is used, the glass transition temperature (Tg) of the obtained molded product is lowered and the heat resistance is lowered.

  In addition, lead has been used as a solder material until now, but in recent years, this lead has flowed into the natural environment from discarded electrical and electronic products, causing serious problems. The use of so-called lead-free solder has not begun. In the future, the use of lead-free solder is thought to increase, but the processing temperature of this lead-free solder is particularly excellent because it is about 10-20 ° C. higher than the processing temperature of conventional solder containing lead. In addition, solder heat resistance is required.

  In light of the above problems, the present inventors have made a reaction between a bifunctional epoxy resin and a phosphorus-containing bifunctional phenol compound in Japanese Patent No. 3412585, ensuring flame retardancy without containing a halogen compound, and solder heat resistance. The present inventors have found a method for achieving compatibility between various properties such as properties and a high glass transition temperature (Tg). Furthermore, in JP-A-2001-348420, it has been found that a higher glass transition temperature (Tg) can be obtained by reacting a phosphorus-containing bifunctional phenol compound, a bifunctional epoxy resin, and a predetermined amount of a polyfunctional epoxy resin. It was.

  However, due to further recent reductions in the thickness and size of electronic devices, printed wiring board materials used in these devices are also required to be thin, and the role as a support is important, and stronger rigidity is required. In particular, as described above, the use of lead-free solder increases the temperature from the conventional reflow temperature, so a material with excellent thermal rigidity is required as a measure for reducing the warpage of the substrate. In this method, it is difficult to achieve both excellent thermal rigidity and solder heat resistance, and none of them has reached the required thermal rigidity level.

  In the above-mentioned Japanese Patent Nos. 3412585 and 2001-348420, most of the phosphorus-containing bifunctional phenol compound is reacted in advance to prepare a pre-reacted epoxy resin, which is further used to prepare an epoxy resin composition. Although a method is disclosed, according to this method, it is possible to suppress a decrease in solder heat resistance and chemical resistance after moisture absorption after molding, which has been a problem in the flame retardant with a conventional additive-type phosphorus compound. did it. In JP-A-2001-348420, it is possible to obtain a molded article having a higher glass transition temperature (Tg) by partially using a polyfunctional epoxy resin in the above reaction. However, in Japanese Patent No. 3412585, 62 to 80% by mass of a pre-reacted epoxy resin is blended with respect to all epoxy resins, and in Japanese Patent Laid-Open No. 2001-348420, a pre-reacted epoxy with respect to all epoxy resins is blended. The resin is blended in an amount of 65% to 66% by mass, and if the pre-reacted epoxy resin is not used in an amount of 60% by mass or more, the solder heat resistance after moisture absorption is lowered. By using a pre-reacted epoxy resin, a cured product having excellent toughness, flexibility, and stress relaxation during heat can be obtained. However, when the pre-reacted epoxy resin is less than 60% by mass, the effect is exhibited. By becoming less.

As a method for improving the rigidity of the substrate, there is a method in which a large amount of an inorganic filler is filled in the resin. In the method of No. 1, if an inorganic filler of 100 parts by mass or more is added to 100 parts by mass of the resin solid content, it becomes difficult to uniformly disperse in the resin, and the resin flow becomes poor and it becomes difficult to mold. It was.
Further, at 100 parts by mass, the rigidity of the substrate is still insufficient, and in order to improve the rigidity of the substrate, it was necessary to add more than that. Therefore, it was difficult to add more inorganic fillers.

  In order to increase the addition of inorganic fillers, the proportion of pre-reacted epoxy resin relative to the whole epoxy resin is reduced, and the epoxy resin is increased by increasing the polyfunctional epoxy resin (melt viscosity at 150 ° C. of about 1 to 10 ps). The overall viscosity becomes low, the amount of inorganic filler can be increased, and the number of polyfunctional components increases, so that a high glass transition temperature (Tg) can be easily obtained. However, in the above method, there is a problem that the solder heat resistance after moisture absorption is lowered when the proportion of the pre-reacted epoxy resin is less than 60% by mass of the entire epoxy resin.

  The present invention has been made in view of the above points, and does not produce a harmful substance at the time of combustion, is excellent in flame retardancy, solder heat resistance after moisture absorption, and excellent in thermal rigidity. An object of the present invention is to provide an epoxy resin composition for a prepreg used for manufacturing a printed wiring board including a printed wiring board, a prepreg using the epoxy resin composition for a prepreg, and a multilayer printed wiring board using the prepreg. It is.

  The epoxy resin composition for prepreg used in the production of the printed wiring board according to claim 1 of the present invention has an average of 1.8 to less than 3 phenolic hydroxyl groups having reactivity with the epoxy resin in the molecule, A phosphorus compound having an average of 0.8 or more phosphorus elements, a bifunctional epoxy resin having an average of 1.8 or more and less than 2.6 epoxy groups in the molecule, and an average of 2.8 epoxy groups in the molecule In the epoxy resin composition containing, as an essential component, a polyfunctional epoxy resin, a curing agent, and an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher as an essential component, the phenolic hydroxyl group of the phosphorus compound and the epoxy resin Is pre-reacted to obtain a pre-reacted epoxy resin, and the epoxy equivalent of the bifunctional epoxy resin is 1.2 equivalents or more relative to 1 equivalent of the phenolic hydroxyl group of the phosphorus compound. The pre-reacted epoxy resin is contained in an amount of 20% by mass or more and 55% by mass or less with respect to the entire epoxy resin, and is represented by the formula (1) as a bifunctional epoxy resin. Selected from biphenyl type epoxy resin, naphthalene type epoxy resin represented by formula (2), special bifunctional epoxy resin represented by formula (3), and dicyclopentadiene-containing bifunctional epoxy resin represented by formula (4) In addition, an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher is blended so as to be 20 parts by mass or more and less than 180 parts by mass with respect to 100 parts by mass of the resin solid content, In addition, the total amount of the inorganic filler is blended so as to be 110 parts by weight or more and less than 200 parts by weight with respect to 100 parts by weight of the resin solid content, and dicyandiamide and / or polyfunctional foam as a curing agent Characterized by using the Nord-based compound.

  Moreover, the epoxy resin composition for prepreg used for the production of the printed wiring board according to claim 2 of the present invention is the pre-reacted epoxy resin in claim 1, wherein the prereactive epoxy resin is 1 equivalent of the phenolic hydroxyl group of the phosphorus compound. The bifunctional epoxy resin is blended and reacted so that the epoxy equivalent of the bifunctional epoxy resin is 1.2 equivalents or more and less than 3 equivalents, and the epoxy equivalent of the polyfunctional epoxy resin is 0.05 equivalents or more and less than 0.8 equivalents. It is characterized by that.

Moreover, the epoxy resin composition for prepreg used for manufacturing the printed wiring board according to claim 3 of the present invention is the inorganic resin other than the inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or more in claim 1. As the filler, either aluminum hydroxide or magnesium hydroxide or both are used.
Moreover, the epoxy resin composition for prepreg used for the manufacture of the printed wiring board according to claim 4 of the present invention is the average as the inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or more in claim 1. Spherical silica having a particle diameter of 0.05 μm or more and 5 μm or less is used.

Moreover, the epoxy resin composition for prepreg used for manufacturing the printed wiring board according to claim 5 of the present invention is characterized in that, in claim 1, the inorganic filler is surface-treated with a coupling agent. And
Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 6 of this invention is the structure of a phosphorus compound in Claim 1, The structure of Formula (5), Formula (6), Formula (7) It is a phosphorus compound represented by either of the following.

  Moreover, the epoxy resin composition for prepregs used for manufacturing the printed wiring board according to claim 7 of the present invention is the prepreg epoxy resin composition according to claim 1, wherein the phosphorus element component content is 0.5% by mass with respect to the entire epoxy resin. It is characterized by being less than 3.5% by mass.

Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 8 of this invention is a polyfunctional epoxy resin in Claim 1, and the benzene ring is connected by bonds other than a methylene bond. A polyfunctional epoxy resin is used.
Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 9 of this invention is a polyfunctional phenol type represented by Formula (8) as a polyfunctional phenol type compound in Claim 1. It is characterized by using a compound.

  Moreover, the epoxy resin composition for prepregs used for manufacture of the printed wiring board which concerns on Claim 10 of this invention is a polyfunctional phenol type represented by Formula (9) as a polyfunctional phenol type compound in Claim 1. It is characterized by using a compound.

  A prepreg according to claim 11 of the present invention is manufactured by impregnating a base material with the epoxy resin composition for prepreg according to any one of claims 1 to 10 and drying and semi-curing it. Features.

A multilayer printed wiring board according to a twelfth aspect of the present invention is formed by laminating the prepreg according to the eleventh aspect on an inner layer substrate on which a circuit pattern is formed.
A prepreg according to claim 13 of the present invention is a blackened epoxy obtained by adding a black pigment and / or a black dye to the epoxy resin composition for prepreg according to any one of claims 1 to 10. It is characterized by being produced by impregnating a resin composition into a substrate and drying and semi-curing it.

  A multilayer printed wiring board according to a fourteenth aspect of the present invention is characterized in that the prepreg according to the thirteenth aspect is laminated and formed on an inner layer substrate on which a circuit pattern is formed.

  The epoxy resin composition for prepreg used in the production of the printed wiring board according to claim 1 of the present invention has an average of 1.8 to less than 3 phenolic hydroxyl groups having reactivity with the epoxy resin in the molecule, A phosphorus compound having an average of 0.8 or more phosphorus elements, a bifunctional epoxy resin having an average of 1.8 or more and less than 2.6 epoxy groups in the molecule, and an average of 2.8 epoxy groups in the molecule In the epoxy resin composition containing, as an essential component, a polyfunctional epoxy resin, a curing agent, and an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher, the phenolic hydroxyl group of the phosphorus compound and the epoxy resin Is pre-reacted to obtain a pre-reacted epoxy resin, and the epoxy equivalent of the bifunctional epoxy resin is 1.2 equivalents or more with respect to 1 equivalent of the phenolic hydroxyl group of the phosphorus compound. The pre-reacted epoxy resin is contained in an amount of 20% by mass or more and 55% by mass or less with respect to the entire epoxy resin, and is represented by the formula (1) as a bifunctional epoxy resin. Selected from biphenyl type epoxy resin, naphthalene type epoxy resin represented by formula (2), special bifunctional epoxy resin represented by formula (3), and dicyclopentadiene-containing bifunctional epoxy resin represented by formula (4) In addition, an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher is blended so as to be 20 parts by mass or more and less than 180 parts by mass with respect to 100 parts by mass of the resin solid content In addition, the total amount of the inorganic filler is blended so as to be 110 parts by weight or more and less than 200 parts by weight with respect to 100 parts by weight of the resin solid content, and dicyandiamide and / or polyfunctional foam as a curing agent Since the use of a nool-based compound, it is not necessary to contain a halogen-based compound such as bromine that causes harmful substances generated during combustion, and flame retardancy can be improved, and the type and content of the inorganic filler can be reduced. By setting the specific range, it is possible to produce a printed wiring board having excellent thermal rigidity without deteriorating the solder heat resistance after moisture absorption.

  Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 2 is an epoxy resin composition of Claim 1, WHEREIN: A pre-reaction epoxy resin is with respect to 1 equivalent of phenolic hydroxyl groups of the said phosphorus compound. The bifunctional epoxy resin has an epoxy equivalent of 1.2 equivalents or more and less than 3 equivalents, and the polyfunctional epoxy resin has an epoxy equivalent of 0.05 equivalents or more and less than 0.8 equivalents. Because of the reaction, both excellent thermal rigidity and solder heat resistance can be achieved.

  Moreover, the epoxy resin composition for prepregs used for manufacture of the printed wiring board which concerns on Claim 3 is an epoxy resin composition of Claim 1, Other than the inorganic filler whose thermal decomposition temperature (5% weight loss) is 400 degreeC or more. Since either one or both of aluminum hydroxide and magnesium hydroxide is used as the inorganic filler, it can contribute to flame retardancy.

  Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 4 is an epoxy resin composition of Claim 1, As a thermal decomposition temperature (5% weight loss) 400 degreeC or more as an inorganic filler, Since spherical silica having an average particle diameter of 0.05 μm or more and 5 μm or less is used, it can be filled more while suppressing the increase in varnish viscosity. Furthermore, the influence on moldability by filling is reduced.

  Further, the epoxy resin composition for prepreg used in the production of the printed wiring board according to claim 5 is the epoxy resin composition according to claim 1, since the inorganic filler is surface-treated with a coupling agent. The secondary agglomeration can be prevented and dispersed uniformly to enhance the adhesive strength with the resin, and the chemical resistance of the filler with poor chemical resistance can be improved.

  Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 6 is an epoxy resin composition of Claim 1, The structure of a phosphorus compound is Formula (5), Formula (6), Formula ( 7) Since it is a phosphorus compound represented by any one of the above, it is not necessary to contain a halogen-based compound such as bromine and the flame retardancy can be improved, and the polymer compound can be reliably reacted with an epoxy resin. It can be produced and the chemical resistance is not lowered.

  Moreover, the epoxy resin composition for prepregs used for manufacture of the printed wiring board which concerns on Claim 7 is an epoxy resin composition of Claim 1, Content of a phosphorus element component is 0.5 mass with respect to the whole epoxy resin. % Or more and less than 3.5% by mass, it is possible to ensure flame retardancy without containing a halogen compound and to suppress heat absorption and to improve heat resistance.

  Moreover, the epoxy resin composition for prepregs used for manufacture of the printed wiring board which concerns on Claim 8 is a epoxy resin composition of Claim 1, and a benzene ring is connected by bonds other than a methylene bond as a polyfunctional epoxy resin. Since the polyfunctional epoxy resin used is used, the viscosity of the epoxy resin composition is low, and the work of impregnating the base material can be performed smoothly. Moreover, since the crosslinking density can be increased while keeping the viscosity low, the glass transition temperature (Tg) of the obtained molded product can be remarkably increased.

  Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 9 is a polyfunctional phenol represented by Formula (8) as a polyfunctional phenol type compound in the epoxy resin composition of Claim 1. Since a system compound is used, a molded product having high heat resistance and a high glass transition temperature (Tg) can be obtained, and further, a UV shielding effect can be imparted.

  Moreover, the epoxy resin composition for prepreg used for manufacture of the printed wiring board which concerns on Claim 10 is a polyfunctional phenol represented by Formula (9) as a polyfunctional phenol type compound in the epoxy resin composition of Claim 1. Since a system compound is used, a molded product having high heat resistance and a high glass transition temperature (Tg) can be obtained.

  A prepreg according to claim 11 is produced by impregnating a base material with the epoxy resin composition for prepreg used in the production of the printed wiring board according to any one of claims 1 to 10, and drying and semi-curing the substrate. Therefore, it exhibits excellent flame retardancy without containing halogen compounds such as bromine, and can obtain characteristics with excellent thermal rigidity without deteriorating solder heat resistance after moisture absorption. is there.

  A multilayer printed wiring board according to claim 12 is formed by laminating the prepreg according to claim 11 on an inner layer substrate on which a circuit pattern is formed, so that it has excellent difficulty without containing a halogen compound such as bromine. In addition to exhibiting flammability, it is possible to obtain characteristics with excellent thermal rigidity without deteriorating solder heat resistance after moisture absorption.

  A prepreg according to claim 13 is obtained by adding an epoxy resin composition blackened by adding a black pigment and / or a black dye to the prepreg epoxy resin composition according to any one of claims 1 to 10. As it is manufactured by impregnating the substrate and drying and semi-curing it, it exhibits excellent flame retardancy without containing halogen compounds such as bromine, and heat resistance without decreasing solder heat resistance after moisture absorption. A characteristic with excellent temporal rigidity can be obtained. Furthermore, UV shielding is also imparted.

  The multilayer printed wiring board according to claim 14 is formed by laminating the prepreg according to claim 13 on the inner layer substrate on which the circuit pattern is formed, and therefore has excellent difficulty without containing a halogen compound such as bromine. In addition to exhibiting flammability, it is possible to obtain characteristics with excellent thermal rigidity without deteriorating solder heat resistance after moisture absorption. Furthermore, the accuracy of the AOI inspection at the time of the inner layer circuit inspection is improved, which is useful. Moreover, UV shielding is also provided.

  Embodiments of the present invention will be described below.

  In the present invention, the phosphorus compound may be any compound having an average of 1.8 to less than 3 phenolic hydroxyl groups having reactivity with the epoxy resin and an average of 0.8 or more phosphorus elements in the molecule. There is no particular limitation. If the average number of phenolic hydroxyl groups in one molecule is less than 1.8, a linear polymer cannot be obtained by reacting with a bifunctional epoxy resin described later. Gelation occurs due to a reaction with a bifunctional epoxy resin or a polyfunctional epoxy resin described later, and the epoxy resin composition cannot be stably adjusted. If the average number of phosphorus elements in one molecule is less than 0.8, sufficient flame retardancy cannot be ensured. The substantial upper limit number of phosphorus elements is 2.5 on average.

  Further, the content of the phosphorus element component is preferably 0.5% by mass or more and less than 3.5% by mass of the entire epoxy resin in the epoxy resin composition, and a halogen compound is added to the epoxy resin within the above range. It is possible to ensure a sufficient flame retardancy without. If the content of the phosphorus element component is less than 0.5% by mass, sufficient flame retardancy may not be obtained. Conversely, if it is 3.5% by mass or more, the molded product is likely to absorb moisture. Or heat resistance may be reduced.

  Particularly preferred as the phosphorus compound is any one of the phosphorus compounds represented by the formula (5), formula (6), and formula (7), and when these are used, they have other bifunctional phenolic hydroxyl groups. Compared with the case of using a phosphorus compound, the flame retardancy and heat resistance of the molded product can be further improved. These may be used alone or in combination of two or more.

  As an epoxy resin, a bifunctional epoxy resin having an average of 1.8 or more and less than 2.6 epoxy groups in one molecule and a polyfunctional epoxy resin having an average of 2.8 or more epoxy groups in one molecule are essential components. Contained as. The bifunctional epoxy resin is not particularly limited as long as the average number of epoxy groups in one molecule is within the above range, but in particular, as the bifunctional epoxy resin, the biphenyl type epoxy resin represented by the formula (1), Any one selected from the naphthalene type epoxy resin represented by the formula (2), the special bifunctional epoxy resin represented by the formula (3), and the dicyclopentadiene-containing bifunctional epoxy resin represented by the formula (4) Is preferred. When these are used, the glass transition temperature (Tg) of the molded product can be increased as compared with the case where a general epoxy resin such as a bisphenol A type epoxy resin is used. In addition, since they have rigidity, the strength during high-temperature heating is good. In addition, in the bifunctional epoxy resin, if the number of epoxy groups in one molecule is less than 1.8 on average, it cannot react with the phosphorus compound to obtain a linear polymer. If it is six or more, it will react with the said phosphorus compound, gelatinization will occur easily, and it will become impossible to adjust an epoxy resin composition stably.

  In addition, other molecular structures are not particularly limited as long as the average number of epoxy groups in one molecule is within the above range. By blending the polyfunctional epoxy resin, an excellent glass transition temperature (Tg) becomes possible. In addition, in the polyfunctional epoxy resin, if the average number of epoxy groups in one molecule is less than 2.8, the crosslinking density of the molded product is insufficient, and the effect of increasing the glass transition temperature (Tg) cannot be obtained.

  Preferable examples of the polyfunctional epoxy resin include phenol novolac type epoxy resins and cresol novolac type epoxy resins, each having an average of 3 or more and less than 5 epoxy groups in one molecule, and a softening temperature of 90 ° C. It is as follows. Since these are all low in reactivity, the viscosity of the epoxy resin composition prepared using these is low, and the impregnation operation to the base material can be performed smoothly. When the softening temperature exceeds 90 ° C., since it is a high molecular weight type resin, gelation is remarkably easily caused by the reaction with the phosphorus compound or the bifunctional epoxy resin, and the epoxy resin composition is stabilized. It may not be possible to adjust.

  Furthermore, as the polyfunctional epoxy resin, a preferable one is a dicyclopentadiene-containing phenol novolac type epoxy resin, and this is also a low reactivity similar to the above phenol novolac type epoxy resin and cresol novolac type epoxy resin. The viscosity of the epoxy resin composition adjusted using this is low, and the work of impregnating the substrate can be performed smoothly. In addition, the glass transition temperature (Tg) of the obtained molded product can be remarkably increased, and adhesion can be improved or moisture absorption can be made difficult.

  Further, as the polyfunctional epoxy resin, preferred are those having an average of 2.8 or more and less than 3.8 epoxy groups in one molecule. This is a polyfunctional epoxy resin having a small average number of epoxy groups, so that even if it reacts with the phosphorus compound or the bifunctional epoxy resin, the molecular weight does not increase rapidly and the viscosity is lowered. The epoxy resin composition can be stably adjusted.

  Particularly preferred as the polyfunctional epoxy resin is a polyfunctional epoxy resin in which the benzene rings are connected by bonds other than methylene bonds. Since this also has low reactivity, the viscosity of the epoxy resin composition prepared by using these is low, and the impregnation work into the base material can be performed smoothly. Moreover, since the crosslinking density can be increased while keeping the viscosity low, the glass transition temperature (Tg) of the obtained molded product can be remarkably increased.

  The above polyfunctional epoxy resins can be used alone or in combination of two or more.

  In the epoxy resin composition according to the present invention, the phosphorus compound and the epoxy resin (both the bifunctional epoxy resin and the polyfunctional epoxy resin or only the bifunctional epoxy resin) are preliminarily reacted in advance. This pre-reacted epoxy resin is obtained by reacting 80% by mass or more of the phosphorus compound used for adjusting the epoxy resin composition with all or part of the epoxy resin used for adjusting the epoxy resin composition. preferable. In preparing the pre-reacted epoxy resin, if the phosphorus compound is less than 80% by mass, a large amount of unreacted phosphorus-containing bifunctional phenolic compound remains, improving the solder heat resistance and chemical resistance after moisture absorption of the molded product. In other words, long-term insulation reliability may be adversely affected.

  Moreover, the said pre-reaction epoxy resin is contained so that it may become 20 to 55 mass% with respect to the whole epoxy resin. If the pre-reaction epoxy resin is less than 20% by mass with respect to the total epoxy resin, the effect of flame retardancy is lost. If the pre-reaction epoxy resin exceeds 55% by mass, the viscosity of the pre-epoxy resin is high. The substrate cannot be filled, and the rigidity of the substrate cannot be obtained.

  Here, the epoxy equivalent of the bifunctional epoxy resin with respect to 1 equivalent of the phenolic hydroxyl group of the phosphorus compound is set to be 1.2 equivalents or more and less than 3 equivalents. By setting in this way, the above-described linear polymer compound can be sufficiently produced, and as a result, a molded product excellent in toughness, flexibility, adhesive strength, and stress relaxation during heating. Can be obtained. In the preparation of the above pre-reacted epoxy resin, if the bifunctional epoxy resin to be blended is less than 1.2 equivalents, the toughness is lost, and the solder heat resistance and chemical resistance after moisture absorption of the molded product can be improved. Conversely, heat resistance and a glass transition temperature are inferior when it is 3.0 equivalents or more. In addition, if the polyfunctional epoxy resin to be blended is less than 0.05 equivalent, the glass transition temperature of the molded product cannot be increased. Conversely, if it is 0.8 equivalent or more, the pre-reacted epoxy resin is stable. You will not be able to get. The epoxy equivalent of the bifunctional epoxy resin is 1.2 equivalents or more and less than 3 equivalents with respect to 1 equivalent of the phenolic hydroxyl group of the phosphorus compound, and the epoxy equivalent of the polyfunctional epoxy resin. By mixing and reacting so that the amount becomes 0.05 equivalent or more and less than 0.8 equivalent, both a high glass transition temperature and solder heat resistance can be achieved.

  In the present invention, an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher is blended so as to be 20 parts by mass or more and less than 180 parts by mass with respect to 100 parts by mass of the resin solids. It mix | blends so that the amount of inorganic fillers may be 110 mass parts or more and less than 200 mass parts with respect to 100 mass parts of resin solid content. In the present invention, the thermal decomposition temperature is measured according to the IPC method. By setting the inorganic filler to the blending range as described above, even when the pre-reacted epoxy resin is less than 60% by mass with respect to the entire epoxy resin, the heat resistance is ensured while ensuring the solder heat resistance after moisture absorption. Can be obtained. When the inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher is less than 20 parts by mass relative to 100 parts by mass of the resin solid content, the effect of improving the solder heat resistance after moisture absorption is poor. In addition, an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher is blended in an amount of 20 parts by mass or more and less than 180 parts by mass with respect to 100 parts by mass of the resin solids, and the inorganic filler is the resin solids If blended so as to be 200 parts by mass or more with respect to 100 parts by mass, the adhesive strength and the like may be reduced.

  As an inorganic filler other than an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher, it is preferable to use either aluminum hydroxide or magnesium hydroxide, or both. By adding such an inorganic filler to the epoxy resin composition, it can contribute to flame retardancy.

  As the inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher, it is preferable to use spherical silica having an average particle size of 0.05 μm or more and 5 μm or less. By using such an inorganic filler, it is possible to fill more while suppressing the increase in the viscosity of the varnish, and further, there is little influence on the moldability, compared with the case where an inorganic filler other than the above is used. Good and preferred. If the average particle size is less than 0.05 μm, the epoxy resin composition may be thickened. On the other hand, if the average particle diameter exceeds 5 μm, the filter that is normally used for removing foreign matters mixed from the external environment or the like may be clogged in the manufacturing process.

  Furthermore, it is preferable that the inorganic filler added to the epoxy resin composition is surface-treated with a coupling agent. By subjecting the inorganic filler to surface treatment, the adhesive strength with the resin can be further strengthened, and further the characteristics of the inorganic filler itself can be improved. Aluminum hydroxide and magnesium hydroxide as inorganic fillers are insufficient in chemical resistance, but chemical resistance can be improved by surface treatment. In addition, when an epoxy silane coupling agent and / or a mercapto silane coupling agent is used for this surface treatment, it is possible to improve properties such as chemical resistance, and to add a secondary inorganic filler in the epoxy resin composition. These can be uniformly dispersed while suppressing aggregation. Here, specific examples of the epoxy silane coupling agent include γ-glycidoxypropyltrimethoxysilane and γ-glycidoxypropylmethyldimethoxysilane, and specific examples of the mercaptosilane coupling agent include γ-mercapto. Mention may be made of propyltrimethoxysilane and γ-mercaptopropyltriethoxysilane.

  As the curing agent, dicyandiamide and / or a polyfunctional phenol-based compound is used. These materials give good electrical properties and harden the linear polymer compound, which is a reaction product of the above-described phosphorus compound having a bifunctional phenolic hydroxyl group and a bifunctional epoxy resin, toughness. In addition, a molded article excellent in flexibility, adhesive strength, and stress relaxation during heating can be obtained. As a polyfunctional phenol type compound, what is represented by the said Formula (8) and Formula (9) is preferable. When these are used, a molded product having high heat resistance and a high glass transition temperature (Tg) can be obtained. Furthermore, it is preferable to use a polyfunctional phenolic compound represented by the formula (8) because the UV shielding effect is imparted.

  In the present invention, in addition to the above components, other epoxy resins, additives, curing accelerators, and various modifiers may be blended in the epoxy resin composition as necessary. For example, a printed wiring board obtained by using a prepreg obtained by impregnating and drying and semi-curing a substrate such as glass cloth with a black pigment and / or black dye added epoxy resin composition, The accuracy of AOI inspection at the time of inner layer circuit inspection is improved and useful. Furthermore, UV shielding is also imparted. Although it does not specifically limit as said black pigment, Carbon black etc. are mentioned. The black dye is not particularly limited, and examples thereof include disazo dyes and azine dyes.

  The curing accelerator is not particularly limited, but tertiary amines and imidazoles may be added.

  Moreover, as a modifier, you may mix | blend rubber components, such as polyvinyl acetal resin, SBR, BR, a butyl rubber, and a butadiene-acrylonitrile copolymer rubber.

  And a varnish can be adjusted by melt | dissolving and diluting the epoxy resin composition obtained as mentioned above in a solvent as needed. A prepreg in a semi-cured state (B-stage) can be produced by impregnating the varnish into a base material and drying the substrate for about 3 to 15 minutes at a temperature of about 120 to 190 ° C., for example. Here, as the base material, craft paper, natural fiber cloth, organic synthetic fiber cloth and the like can be used in addition to glass fiber cloth such as glass cloth, glass paper, and glass mat.

  Moreover, a laminated board can be manufactured by stacking the required number of prepregs manufactured in this way and heating and pressing the prepregs under conditions of 140 to 200 ° C. and 0.98 to 4.9 MPa, for example. is there. At this time, a metal foil-clad laminate can be produced by stacking a metal foil on one or both sides of a predetermined number of prepregs and heating and pressing the prepreg and the metal foil together. As this metal foil, copper foil, silver foil, aluminum foil, stainless steel foil or the like can be used. In addition, by arranging prepregs on the upper and lower surfaces of the inner layer substrate on which the circuit pattern has been formed in advance, overlaying the metal foil on one or both sides of the required number of prepregs, and heating and pressing the prepreg and the metal foil together A multilayer printed wiring board can be manufactured.

  Hereinafter, the present invention will be specifically described by way of examples.

  First, the epoxy resin, curing agent, phosphorus compound, inorganic filler, solvent, and blackening agent used are shown below in order.

The following eight types of epoxy resins were used.
Epoxy resin 1: Tetramethylbiphenyl type bifunctional epoxy resin “YX4000H” manufactured by Japan Epoxy Resin Co., Ltd.
In formula (1), n = 1 (epoxy group average 2.0, epoxy equivalent 195)
Epoxy resin 2: biphenyl type bifunctional epoxy resin “YL6121” manufactured by Japan Epoxy Resin Co., Ltd.
A mixture of n = 0,1 in the chemical formula (1) (2.0 epoxy groups on average, epoxy equivalent 172)
Epoxy resin 3: Naphthalene type bifunctional epoxy resin of Chemical formula (2) “EPICLON-HP4032” manufactured by Dainippon Ink & Chemicals, Inc.
(Epoxy group average 2.0, epoxy equivalent 150)
Epoxy resin 4: Dicyclopentadiene-containing bifunctional epoxy resin of Chemical formula (4) “ZX-1257” manufactured by Tohto Kasei Co., Ltd.
(Epoxy group average 2.0, epoxy equivalent 257)
Epoxy resin 5: a polyfunctional epoxy resin in which the benzene rings are connected by bonds other than methylene bonds "EPPN502H" manufactured by Nippon Kayaku Co., Ltd.
(Melt viscosity of about 5 ps at 150 ° C)
(Epoxy group average 7.0, epoxy equivalent 170)
Epoxy resin 6: A polyfunctional epoxy resin in which benzene rings are connected by bonds other than methylene bonds "VG3101" manufactured by Mitsui Petrochemical Co., Ltd.
(Epoxy equivalent 219)
(Melt viscosity of about 4 ps at 150 ° C.)
Epoxy resin 7: a polyfunctional epoxy resin in which benzene rings are connected by bonds other than methylene bonds "FSX-220" manufactured by Sumitomo Chemical Co., Ltd.
(Epoxy equivalent 220)
(Melt viscosity of about 4 ps at 150 ° C.)
Epoxy resin 8: phenol novolac type polyfunctional epoxy resin “EPICLON-N740” manufactured by Dainippon Ink & Chemicals, Inc.
(Epoxy equivalent 180)
(Melt viscosity at 150 ° C. about 3 ps)

Moreover, the following four types of curing agents were used.
Curing agent 1: Dicyandiamide Reagent (Molecular weight 84, theoretically active hydrogen equivalent 21)
Hardener 2: Multifunctional phenolic resin “MEH7600” manufactured by Meiwa Kasei Co., Ltd.
(Phenolic hydroxyl group equivalent 100)
Structural formula (8)
Curing agent 3: Multifunctional phenolic resin “MEH7500H” manufactured by Meiwa Kasei
(Phenolic hydroxyl group equivalent 100)
Structural formula (9)
Curing agent 4: polyfunctional phenolic resin TD-2093Y manufactured by Dainippon Ink & Chemicals, Inc.
(Phenolic hydroxyl group equivalent 105)
Phenol novolac type phenol

Moreover, the following three types of phosphorus compounds were used.
Phosphorus compound 1: Compound of formula (7) having an average of 2.0 phenolic hydroxyl groups
"HCA-HQ" manufactured by Sanko Co., Ltd.
(Phosphorus content: about 9.6% by mass, hydroxyl group equivalent: about 162)
Phosphorus compound 2: “HCA-NQ” manufactured by Sanko Co., Ltd., compound of formula (6) having an average of 2.0 phenolic hydroxyl groups
(Phosphorus content about 8.2% by mass, hydroxyl group equivalent about 188)
Phosphorus compound 3: Compound of formula (5) having an average of 2.0 phenolic hydroxyl groups (diphenylphosphinyl hydroquinone)
"PPQ" manufactured by Hokuko Chemical Co., Ltd.
(Phosphorus content about 10.1% by mass, hydroxyl group equivalent about 155)

The following 10 types of inorganic fillers were used.
Inorganic filler 1: Aluminum hydroxide "Hijiride H42M" manufactured by Showa Denko KK
(Average particle size: about 1 μm Thermal decomposition temperature: 265 ° C.)
Inorganic filler 2: Aluminum hydroxide “C302A” manufactured by Sumitomo Chemical Co., Ltd.
(Average particle size: about 2 μm Thermal decomposition temperature: 280 ° C.)
Inorganic filler 3: Aluminum hydroxide “C305” manufactured by Sumitomo Chemical Co., Ltd.
(Average particle size: about 5 μm Thermal decomposition temperature: 270 ° C.)
Inorganic filler 4: Magnesium hydroxide “Kimas 5” manufactured by Kyowa Chemical Industry Co., Ltd.
(Average particle size: about 1 μm Thermal decomposition temperature: 360 ° C.)
Inorganic filler 5: Spherical silica “Kicross MSR-04” manufactured by Tatsumori Co., Ltd.
(Average particle size: about 4.1 μm Thermal decomposition temperature: 500 ° C. or higher)
Inorganic filler 6: spherical silica “FB-1SDX” manufactured by Denka
(Average particle size: about 1.5 μm Thermal decomposition temperature: 500 ° C. or higher)
Inorganic filler 7: Spherical silica “SFP-30M” manufactured by Denka
(Average particle size: about 0.72 μm Thermal decomposition temperature: 500 ° C. or higher)
Inorganic filler 8: spherical silica “FB-945X” manufactured by Denka
(Average particle size: about 11.6 μm Thermal decomposition temperature: 500 ° C. or more)
Inorganic filler 9: spherical silica “SO-C2” manufactured by Admatechs
(Average particle size: about 0.5 μm Thermal decomposition temperature: 500 ° C. or higher)
Inorganic filler 10: Inorganic filler 3 (100 parts by mass) coupling agent (epoxysilane coupling agent γ-glycidoxypropyltrimethoxysilane Shin-Etsu Chemical Co., Ltd. “KBM403” approximately 1.5 parts by mass) Surface treatment by dry method

Moreover, the following were used for the hardening accelerator.
Curing accelerator 1: “2-ethyl-4-methylimidazole” manufactured by Shikoku Kasei Co., Ltd.

Moreover, the following three types of solvents were used.
Solvent 1: methyl ethyl ketone (MEK)
Solvent 2: Methoxypropanol (MP)
Solvent 3: Dimethylformamide (DMF)

Moreover, the following were used for the black agent.
Blacking agent 1 “Adallite DW-07” manufactured by Ciba Specialty Chemicals

  And using said epoxy resin, a phosphorus compound, etc., eight types of pre-reaction epoxy resins were prepared as shown below.

(Preliminary reaction epoxy resin 1)
Epoxy resin 1 (70 parts by mass) and phosphorus compound 1 (30 parts by mass) are heated and stirred in a mixed solvent of 115 ° C. solvent 2 (64.0 parts by mass) and solvent 3 (2.67 parts by mass), and then By adding 0.2 parts by mass of triphenylphosphine and continuing heating and stirring for about 5 hours, the epoxy equivalent in the solid content is about 500, the solid content is 60% by mass, and the phosphorus content in the solid content is about 2. A pre-reacted epoxy resin 1 having a melt viscosity of about 110 ps at 9% by mass and a solid content of 150 ° C. was obtained.

(Preliminary reaction epoxy resin 2)
Epoxy resin 1 (60.9 parts by mass), epoxy resin 5 (9.3 parts by mass), and phosphorus compound 1 (29.8 parts by mass) were heated and stirred in solvent 2 (53.8 parts by mass) at 115 ° C. Then, by adding 0.2 parts by mass of triphenylphosphine and continuing heating and stirring for about 8 hours, the epoxy equivalent in the solid content is about 540, the solid content is 65% by mass, the phosphorus content in the solid content is about A pre-reacted epoxy resin 2 having a melt viscosity of about 200 ps at 2.9% by mass and a solid content of 150 ° C. was obtained.

(Pre-reacted epoxy resin 3)
Epoxy resin 2 (67 parts by mass) and phosphorus compound 1 (33 parts by mass) are heated and stirred at 130 ° C. in the absence of a solvent, and then 0.2 parts by mass of triphenylphosphine is added, followed by heating and stirring for about 4 hours. By continuing, the pre-reaction epoxy resin 3 having an epoxy equivalent of about 500 and a melt viscosity of about 100 ps at 150 ° C. was obtained.

(Preliminary reaction epoxy resin 4)
Epoxy resin 3 (70 parts by mass) and phosphorus compound 3 (30 parts by mass) are heated and stirred at 130 ° C. without solvent, and then 0.2 parts by mass of triphenylphosphine is added, followed by heating and stirring for about 4 hours. By continuing, the pre-reaction epoxy resin 4 having an epoxy equivalent of about 300 and a melt viscosity of about 100 ps at 150 ° C. was obtained.

(Preliminary reaction epoxy resin 5)
Epoxy resin 4 (75 parts by mass) and phosphorus compound 1 (25 parts by mass) are heated and stirred at 130 ° C. in the absence of a solvent, and then 0.2 parts by mass of triphenylphosphine is added, followed by heating and stirring for about 4 hours. By continuing, the pre-reaction epoxy resin 5 having an epoxy equivalent of about 420 and a melt viscosity of about 120 ps at 150 ° C. was obtained.

(Preliminary reaction epoxy resin 6)
Epoxy resin 1 (70 parts by mass) and phosphorus compound 2 (30 parts by mass) are heated and stirred at 130 ° C. in the absence of a solvent, and then 0.2 parts by mass of triphenylphosphine is added, followed by heating and stirring for about 4 hours. By continuing, the pre-reaction epoxy resin 6 having an epoxy equivalent of about 540 and a melt viscosity of about 500 ps at 150 ° C. was obtained.

(Preliminary reaction epoxy resin 7)
Epoxy resin 1 (70 parts by mass) and phosphorus compound 1 (30 parts by mass) were heated and stirred in solvent 2 (53.8 parts by mass) at 115 ° C., and then 0.2 parts by mass of triphenylphosphine was added. By continuing heating and stirring for about 10 hours, the epoxy equivalent in the solid content is about 550, the solid content is 65% by mass, the phosphorus content in the solid content is about 2.9% by mass, the melt viscosity at about 150 ° C. 130 ps of pre-reacted epoxy resin 7 was obtained.

(Preliminary reaction epoxy resin 8)
Epoxy resin 1 (58.6 parts by mass), epoxy resin 5 (6.9 parts by mass) and phosphorus compound 1 (34.5 parts by mass) were heated and stirred in solvent 2 (53.8 parts by mass) at 115 ° C. Then, by adding 0.2 parts by mass of triphenylphosphine and continuing heating and stirring for about 8 hours, the epoxy equivalent in the solid content is about 530, the solid content is 65% by mass, and the phosphorus content in the solid content is about A pre-reacted epoxy resin 8 having a melt viscosity of about 150 ps at 150 ° C. with a solid content of 3.3% by mass was obtained.

  And in preparing an epoxy resin composition using the above, pre-reacted epoxy resin, other epoxy resin or phosphorus compound, inorganic filler, curing agent, solvent, other additives are added, and special Mix for about 120 minutes at about 1000 rpm with "Homomixer" manufactured by Kika Kogyo Co., Ltd., mix with a curing accelerator, stir again for 30 minutes, and then disperse the inorganic filler using "Nanomill" manufactured by Asada Tekko To obtain a varnish.

  Thus, the epoxy resin composition for prepregs of Examples 1-12 and Comparative Examples 1-4 was obtained with the compounding amounts shown in Tables 1-5. Then, using the obtained epoxy resin composition, a prepreg, a copper clad laminate, and a multilayer laminate were produced as follows. In Tables 1 to 5, the preliminary reaction resin indicates a preliminary reaction epoxy resin.

<Method for producing prepreg>
The epoxy resin composition prepared as described above is impregnated into glass cloth (WETA116E thickness 0.1 mm, manufactured by Nittobo Co., Ltd.) as a varnish, and dried in a dryer at 120 ° C. to 190 ° C. for about 5 to 10 minutes. This produced a semi-cured (B-stage) prepreg. In Example 5, the epoxy resin composition for prepreg was blackened by blending 10 parts by mass of the black agent 1.

<Method for producing copper-clad laminate>
One, two, or eight prepregs manufactured as described above are stacked, and copper foil is stacked on both sides of the prepreg, and this is heated and heated under conditions of 140 to 180 ° C. and 0.98 to 3.9 MPa. By pressing, a copper-clad laminate having a thickness of about 0.1 mm, about 0.2 mm, and about 0.8 mm was produced. Here, the heating time was set so that the time when the entire prepreg was 160 ° C. or higher was at least 90 minutes. At this time, the inside of the press was in a reduced pressure state of 133 hPa or less. By doing so, the adsorbed water of the prepreg can be efficiently removed, and voids (voids) can be prevented from remaining after molding. The copper foil used was “GT” (thickness 0.018 mm) manufactured by Furukawa Circuit Foil Co., Ltd.

<Method for producing multilayer laminate>
Also, the inner layer treatment was performed on the copper foil (thickness 18 μm) patterned on the inner layer substrate (copper-clad laminate thickness 0.2 mm produced above), and then the upper and lower surfaces of the inner layer substrate A prepreg was placed one by one, and a copper foil was laminated on both prepregs, and molded under the same molding conditions as above to produce a multilayer laminate.

  And the physical property evaluation as shown below was performed about the molded article obtained as mentioned above.

<Flame retardance, average number of seconds for extinction>
The copper foil on the surface was removed by etching from a copper clad laminate having a thickness of 0.2 mm, and this was cut into a length of 125 mm and a width of 13 mm. Carried out. In addition, the average time from ignition to extinction was measured in order to see the difference in flame retardant properties.

<Glass transition temperature (Tg)>
The copper foil on the surface was removed from the 0.8 mm thick copper clad laminate by etching, this was cut into a length of 30 mm and a width of 5 mm, tan δ was measured with a viscoelastic spectrometer device, and the peak temperature was determined as Tg. It was.

<Boiled solder heat resistance>
The copper foil was removed from the multilayer laminate including the inner layer substrate in the same manner as described above, and five sheets of this were cut into 50 mm squares, and these were prepared at 100 ° C. for 2 hours, 4 hours, and 6 hours. After boiling, it was immersed in a soldering bath at 288 ° C. for 20 seconds, and then appearance abnormalities such as swelling were observed. In addition, the observation result made the thing with (circle), the thing with a small dandruff (triangle | delta), and the thing with a big dandruff made x with the thing without a blister.

<Heat flexural modulus>
A copper clad laminate with a thickness of 0.8 mm was removed from the copper clad laminate in the same manner as described above, and this was cut into a length of 100 mm and a width of 25 mm, and an atmosphere at 250 ° C. according to JIS C6481 The thermal flexural modulus was measured below.

<UV shielding rate>
A copper-clad laminate having a thickness of 0.1 mm was used as a sample after removing the copper foil from the copper-clad laminate in the same manner as described above. First, the UV amount generated from the ultra-high pressure mercury lamp is first measured (initial value) with a UV sensor (measurement wavelength is 420 nm). Next, the sample obtained above was sandwiched between them, the UV amount was measured (sample value) by the same method, and the UV shielding rate was obtained by the following formula.

UV shielding rate (%) = (sample value / initial value) × 100

<Heat resistance>
A copper-clad laminate with a thickness of 0.2 mm was prepared by cutting it into 50 mm squares, and the heat resistance was measured according to JIS C6481.

  The results of the above physical property evaluation are summarized in Tables 1 to 5.

  Comparative Example 1 and Comparative Example 2 are examples in which the proportion of the pre-reacted epoxy resin exceeds 60% by mass and the content of the filler is small, and these have a thermal rigidity (elastic modulus during heating) as compared with the examples. It turns out that it is low.

  Comparative Example 3 is a system in which the proportion of the pre-reacted epoxy resin is less than 60% by mass with respect to the entire epoxy resin, and the inorganic filler is simply increased, but the thermal rigidity (thermal bending elastic modulus) increases. It can also be seen that the solder heat resistance is reduced. On the other hand, as shown in Examples, in a system in which an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher is blended in an amount of 20 parts by mass or more and less than 180 parts by mass with respect to 100 parts by mass of the resin solid content It can be seen that the thermal rigidity and the solder heat resistance are compatible.

  Comparative Example 4 is a system in which the inorganic filler is increased as compared to Comparative Example 2. However, since the pre-reacted epoxy resin is present in an amount of 60% by mass or more based on the entire epoxy resin, the viscosity of the entire epoxy resin is high, It can be seen that when an inorganic filler is added in such an amount that the rigidity is obtained (100 parts by mass or more with respect to 100 parts by mass of the resin solid content), voids remain and a copper-clad laminate cannot be produced.

  Examples 3, 7, 9, and 12 are systems using the polyfunctional phenolic curing agent shown in Chemical Formula 8 as the curing agent, and the UV shielding property is improved as compared with other examples. I understand. Furthermore, it turns out that the glass transition temperature (Tg) has improved compared with Example 11 which used the phenol novolak type polyfunctional phenol for the hardening | curing agent.

  In addition, Example 5 is a system using the polyfunctional phenolic curing agent shown in Chemical Formula 9 as the curing agent, and has a glass transition temperature (Tg) as compared with Example 11 using a phenol novolac type polyfunctional phenol as the curing agent. ) Is improved. Furthermore, Example 5 is a system using a black agent, and it can be seen that the UV shielding property is improved as compared with other Examples.

  Examples 1, 2, 4, 6, and 8 are systems using a polyfunctional epoxy resin in which a benzene ring is connected to a polyfunctional epoxy resin by a bond other than a methylene bond, and a phenol novolac type polyfunctional epoxy resin. It can be seen that the glass transition temperature (Tg) is improved as compared with Example 10 in which

In addition, Example 12 is a system in which aluminum hydroxide or magnesium hydroxide is not used for the inorganic filler, and it can be seen that the flame retardancy is low as compared with Example 9 using aluminum hydroxide.

Claims (14)

Phosphorus compounds having an average of 1.8 to less than 3 phenolic hydroxyl groups having reactivity with the epoxy resin in the molecule and an average of 0.8 or more phosphorus elements; Bifunctional epoxy resin having 8 or more and less than 2.6, polyfunctional epoxy resin having an average of 2.8 or more epoxy groups in the molecule, curing agent, thermal decomposition temperature (5% weight loss) inorganic at 400 ° C or higher In an epoxy resin composition containing a filler as an essential component, a phenolic hydroxyl group of the phosphorus compound is reacted in advance with the epoxy resin to obtain a pre-reacted epoxy resin, and 1 equivalent of the phenolic hydroxyl group of the phosphorus compound The bifunctional epoxy resin has an epoxy group equivalent of 1.2 equivalents or more and less than 3 equivalents, and the pre-reaction epoxy resin is 20% by mass or less based on the total epoxy resin. The bifunctional epoxy resin is a biphenyl type epoxy resin represented by the formula (1), a naphthalene type epoxy resin represented by the formula (2), and a formula (4). What is selected from the dicyclopentadiene-containing bifunctional epoxy resin represented is further blended, and an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher is 20 masses with respect to 100 mass parts of resin solid content. And dicyandiamide as a curing agent, blended so that the total inorganic filler amount is 110 parts by weight or more and less than 200 parts by weight with respect to 100 parts by weight of the resin solid content. And / or an epoxy resin composition for prepreg used in the production of a printed wiring board, wherein a polyfunctional phenolic compound is used.

The epoxy equivalent of the bifunctional epoxy resin is 1.2 equivalents or more and less than 3 equivalents with respect to 1 equivalent of the phenolic hydroxyl group of the phosphorus compound, and the epoxy equivalent of the polyfunctional epoxy resin. The epoxy resin composition for prepreg used in the production of a printed wiring board according to claim 1, wherein the composition is made to react so as to be 0.05 equivalent or more and less than 0.8 equivalent. 2. The print according to claim 1, wherein one or both of aluminum hydroxide and magnesium hydroxide is used as an inorganic filler other than an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or more. An epoxy resin composition for prepreg used for production of a wiring board. A spherical silica having an average particle diameter of 0.05 μm or more and 5 μm or less is used as an inorganic filler having a thermal decomposition temperature (5% weight loss) of 400 ° C. or higher. The printed wiring board according to claim 1 is used. Epoxy resin composition for prepreg. 2. The epoxy resin composition for prepreg used in the production of a printed wiring board according to claim 1, wherein the inorganic filler is surface-treated with a coupling agent. The prepreg used for manufacturing a printed wiring board according to claim 1, wherein the structure of the phosphorus compound is a phosphorus compound represented by any one of the formulas (5), (6), and (7). Epoxy resin composition.

2. The epoxy resin for prepreg used in the production of a printed wiring board according to claim 1, wherein the content of the phosphorus element component is 0.5% by mass or more and less than 3.5% by mass with respect to the entire epoxy resin. Composition. 2. The epoxy resin composition for prepreg used in the production of a printed wiring board according to claim 1, wherein the multifunctional epoxy resin is a multifunctional epoxy resin in which benzene rings are connected by bonds other than methylene bonds. The polyfunctional phenolic compound represented by Formula (8) is used as a polyfunctional phenolic compound, The epoxy resin composition for prepregs used for manufacture of the printed wiring board of Claim 1 characterized by the above-mentioned.

The polyfunctional phenolic compound represented by Formula (9) is used as the polyfunctional phenolic compound. The epoxy resin composition for prepreg used in the production of a printed wiring board according to claim 1.

A prepreg produced by impregnating a base material with the epoxy resin composition for prepreg according to any one of claims 1 to 10, followed by drying and semi-curing. A multilayer printed wiring board, wherein the prepreg according to claim 11 is laminated and formed on an inner layer substrate on which a circuit pattern is formed. The substrate is impregnated with the epoxy resin composition blackened by adding a black pigment and / or a black dye to the epoxy resin composition for prepreg according to any one of claims 1 to 10, and dried and semi-cured. A prepreg characterized by being manufactured. A multilayer printed wiring board, wherein the prepreg according to claim 13 is laminated and formed on an inner layer substrate on which a circuit pattern is formed.